Press with movable table,in particular punching press



United States Patent Inventor Artorige Chiesa Genoa, Italy Appl. No. 708,552

Filed Feb. 27, I968 Patented Sept. 1, 1970 Priority March 3, 1967 Italy PRESS WITH MOVABLE TABLE, IN PARTICULAR PUNCHING PRESS 4 Claims, 4 Drawing Figs.

US. Cl 83/533, 83/535 Int. Cl 826d 5/02,

Primary Examiner-William S. Lawson Atl0rneyStowell and Stowell ABSTRACT: A press, in particular a punching press, wherein the vertically reciprocating upper table is linked to its driving mechanism, that is operatively supported by a base frame. so that, during a period of inoperation of the press, the upper table can be displaced laterally away from its vertically overlying and confronting operational position with respect to the bottom table on the base frame.

R m m w L/ H I p u //L L 4 u m r f a E. F yt C m i}- w 3% M i O O 3 Q E P o F 0 O m *0 iivmfiurpfl- D M v ARTORIGE CHESA ATTORNEYS PRESS WITH MOVABLE TABLE, IN PARTICULAR PUNCHING PRESS The present invention concerns a press and in particular a press for punching or cutting materials such as skins, plastics, fabrics and so on.

In considering the invention with reference to a punching press, it is known that the tool or punch of such press has to be put on the sheet or object to be cut according to a preestablished and advantageous position so as to utilize the greatest possible part of the material of the object. The same is true when the object is to be formed by using several tools which have to be arranged in a certain position. Such conditions require that the operating blade of the hollow punch, located on the sheet or object to be cut, can be easily and entirely observed by the operator. Therefore, it is obvious that such presses must be provided with a movable upper table. Generally this condition is complied with by linking the upper table of the press to one of the ends of an arm with the other end of said arm being linked to a column so as to allow the lateral dislocation of the table and thereby provide free and easy access to the surface of the lower table which supports the block of the material to be cut and the hollow punch. Such known presses are capable of satisfying the above mentioned requirements, but on the other hand, such presses are not capable of exerting the certain efforts, which are required to punch objects with large surfaces and/or resistant materials having considerable thickness, or superimposed materials. Furthermore, such known presses are not able to carry out precise work, as required in some cases, due to the unavoidable deflections induced in the upper overhanging table.

This invention provides means for avoiding the above mentioned drawbacks while permitting, moreover, the cutting of resistant and compact materials, even where the surface to be cut is very large, without submitting the press to abnormal stresses. In particular, the invention ensures the parallelism of the tables, as well correct guided movement of the movable table (which is, generally speaking, the upper table) relative to the fixed table (which is, generally speaking, the lower table). Also, if the tool is arranged in the neighborhood of any of the press ends, this is accomplished without hindering or disturbing either the setting of the tool in its proper position or the adjustment thereof.

The press, according to the invention, is characterized in that its upper table is linked to the frame by means of movable connecting members, allowing the displacement of the table, in such a way as to move it laterally away from the lower table.

In practice, in carrying out the inventive idea, several embodiments of the press can be realized within the scope of protection afforded by the present invention. For instance, the upper table can be movable and therefore linked to the driving equipment of the press and can be displaced with respect to the lower table, by means of hinges, or otherwise, by rollers moving along guides extending on a substantially horizontal direction from one of the longitudinal sides of the press. The invention will now be explained in the following ,description, in which reference is made to the attached drawing, illustrating, by way of example, two presses, embodying the principles of this invention, and in which:

FIGS. 1 and 2 are front and side elevational views, respectively, of the press equipped with a movable bridge arrangement whereby the upper table can be angularly swung laterally out of its normal operating position in relation to the fixed lower table.

FIGS. 3 and 4 are front and side elevational views, respectively, ofa modified form ofthe press, wherein the upper table is slidably movable in a lateral direction from its normal operating position in relation to the fixed lower table.

With reference to FIGS. 1 and 2, the illustrated press includes a box-shaped frame A, which houses the pumps, the cylinder-piston units, the movable parts of which are connected to the columns or rams B which are slidably guided in their vertically reciprocal movement by guides C formed in frame A. The upper ends of the columns B are each provided with a crosshead or cross-member D that cooperate to constitute the press bridge.

According to the present invention, each crosshead D is provided near its top end with one leaf of a hinge member F, the hinge members F being aligned so that the pivot pins of said members are co-axial and horizontal and preferably arranged at the upper part of the forward part of the press.

The other or companion leaf plates of hinges F are connected to a square-shaped frame G which is swingably mounted between the crossheads D. Thus, the hinge members F have, in effect, apertured cars which project from the tops of the crossheads and extend laterally therefrom and cooperate with companion apertured ears on the frame G with the pivot pins connecting the ears at each end of the frame G to the crossheads D so that the hinge members mount the frame G between the crossheads D. The frame G supports at its lower end, a plate or table H which constitutes the upper plate or table of the press and which, in this case, is a movable plate or table.

From the foregoing, it can be clearly understood that frame G can be oscillated, in the direction of arrow X shown in FIG. 2, about the pivot pins of hinges F. In this way the upper plate or table H is moved away from the lower plate or table K, which is fixed on the frame A, and moved into the position B so as to allow easy access to said lower plate or table, as well as permitting easy locating of the tools in the desired position on the sheet to be cut.

The displacement of frame G with respect to crossheads D can be effected by means of suitable hand or hydraulically operated controls. For instance, in the illustrated case, it is possible to perform said displacement advantageously by means of screw-and-nut units or by means of hydraulic jacks, arranged between the crossheads D and frame G.

To prevent faulty operations when the plate or table II is displaced with respect to its normal working position vertically overlying and confronting the fixed lower plate or table K it is possible to provide the press with locking members, which are automatically operated by means of an upsetting or releasing motion of said table H, said members preventing, at the same time, the displacement of the press movable table. Similar locking members can be provided between frame A and the movable table (which can be lower table K) said members being operated when said movable table is in its active or operating state and away from the fixed table, to prevent the displacement of the upper table H. The above mentioned locking member can be either of the mechnical or electromechanical type.

In the embodiment according to FIGS. 3 and 4, parts like those shown in FIGS. 1 and 2 bear the same reference numerals. In this case, each crosshead D is equipped with horizontal guides L that are mounted by brackets M, the latter projecting from the back part of the press.

Roller units N are fixed to the side walls of a frame or carriage P having on its lower part the upper plate or table II of the press. The roller units roll along the above mentioned guides to support the frame P for sliding movement laterally relative to the base frame A.

In this case, it is possible to move the upper table II completely away from the lower table A into position II shown in FIG. 4 by sliding the frame P straight out with the supporting rollers N rolling on the fixed guides L.

The displacement of frame P can be effected by means of mechanical controls (pinion-toothed rack) or by hydraulic means, whereby the displacement of said pagts can be controlled, depending on the position taken each time by such parts, and braking members can function to prevent a faulty operation, as explained with reference to FIGS. 1 and 2.

The inventive teaching, as illustratively disclosed in the foregoing, can be applied to any kind of bridge presses, the upper part of which can be either fixed or movable. Such presses can be completed with other safety or locking devices to avoid possible damage and to stop the table at the end of its cutting stroke.

It is, however, understood that it is possible to alter the embodiment details as well as the end use or purpose of the press, within the limits of the present invention and therefore within the scope of the appended claims.

I claim:

1. A press comprising a base frame, a lower table supported by the base frame, an upper table vertically overlying the lower table, said tables being operatively disposed in parallel horizontal planes and being movable vertically relative to each other in pressing relationship, means attaching the upper table to the base frame and means connecting the upper table to said attaching means for lateral movement of the upper table, during non-operation of the press, away from the lower table and out of its normal overlying pressing position with respect to the lower table, said means attaching the upper table to the base frame including vertically reciprocating ram elements so that the upper table is movable vertically relative to the base frame, said lower table being fixedly supported on the base frame, said connecting means connecting the upper table to the ram elements, said upper table being carried by a frame secured by the connecting means to the ram elements, said connecting means including pivot means secured between the upper table frame and the ram elements.

2. A press according to claim 1 wherein said base frame has opposing ends, said ram elements being disposed at said ends and being vertically reciprocable at said ends, said upper table frame being positioned between the ram elements and having an underside to which the upper table is attached and said pivot means including hinges connecting the ram elements to the ends ofthe upper table frame.

3. A press according to claim 2 wherein said ram elements have upper crossheads between which the upper table frame is longitudinally positioned, said upper table frame having opposing ends and a longitudinal vertical wall extending between the ends, and said hinges including hinge ears attached to the longitudinal wall of said frame adjacent the end walls thereof and extending normally of the longitudinal wall of said frame and companion hinge ears carried by the crossheads and pivot pins joining the ears with the pivot pins being coaxially disposed parallel with and outwardly from the longitudinal wall of said frame.

4. A press comprising a base frame having interconnected and longitudinally spaced apart, opposing vertical end portions, a longitudinal top extending between the end portions, a lower table fixedly supported on the top, said end portions having outer sides provided with fixed vertically disposed internally receptive guides, supporting columns guidingly and supportingly slidably mounted in the guides and movable ver' tically relative thereto and having upper end portions, an upper crosshead integral with the upper end portion of each of the columns and having an inner surface, a supporting arm transversely fixed on the inner surface of each crosshead and having an end projection laterally extending from the crosshead, means carried by the crossheads for supporting the end projections, said end projections laterally projecting from each crosshead in the same direction with the end projections extending transversely of the longitudinal axis of the base frame, said arms and their end projections having coplanar supporting tracks arranged transversely of the base frame, a movable frame longitudinally positioned between the crossheads and having an underside, an upper table fixed to the underside, said movable frame having opposing ends, and supporting guide rollers carried by said ends and rollingly mounted on the tracks whereby said movable frame is mounted for movement from a position vertically offset from the lower table to a position vertically overlying the lower table with the upper and lower tables being in vertical confronting relation and said columns being adapted to then receive a driving motion that aided by the carried weight of the crossheads and the movable frame is adapted to pressingly force the upper table relative to the fixed lower table. 

